A quenching system and method for wind power main bearing machining

Abstract

This invention relates to the field of heat treatment technology for large bearings, and discloses a quenching system and method for processing wind turbine main bearings. The system includes an industrial control computer, a main support system, a power supply system, a water system, and a control and monitoring system. These systems work collaboratively through mechanical and electrical connections. The main support system includes a turntable and several columns symmetrically arranged around the turntable. Induction heating coils are installed on the columns, and a worktable is located at the bottom of the turntable. This quenching system for processing wind turbine main bearings, through multi-system collaborative design and modular control, solves many technical pain points of traditional quenching equipment for processing large wind turbine main bearings. It significantly improves processing efficiency, quenching quality, equipment stability, and resource utilization, achieving full-process automated control and parameter traceability, and greatly enhancing the industrial application value and process adaptability of the equipment.

Description

Technical Field

[0001] This invention relates to the field of heat treatment technology for large bearings, specifically a quenching system and method for processing wind turbine main bearings. Background Technology

[0002] Large bearings play a crucial supporting role in various heavy machinery and equipment. Their main function is to bear radial and axial loads and reduce rotational friction through rolling contact. Because they operate under high load and high speed conditions, the inner and outer rings of the bearings must have high hardness and wear resistance to ensure long service life and high performance.

[0003] To meet the requirements for high hardness and high wear resistance, the inner and outer rings of large bearings are typically hardened. The hardening process alters the microstructure of the material through rapid heating and cooling, thereby significantly improving its hardness and wear resistance.

[0004] In existing technologies, large bearings are mostly hardened by scanning quenching. For machining large workpieces, the processing speed is too slow. Moreover, continuous and uninterrupted quenching of large workpieces requires high-frequency power supplies to run at full load for a long time, which can easily lead to overheating of the equipment and requires an additional cooling system. Compared with traditional quenching methods, bainitic integral quenching requires slow cooling to the isothermal region at the critical cooling rate. It is easy for pearlite or martensite to be mixed in due to improper selection of cooling medium, which reduces the processing effect.

[0005] For example, Chinese patent CN222160239U describes a non-soft belt quenching machine tool. The core of this solution consists of a machine tool base, a machine tool lower fixed table, a rotation drive device (including a mounting plate, connecting rod, fixed plate, rotation motor, and rotation rod), a heating ring, a power distribution box, an electric lifter, a linear driver, a fixed frame and a lifting frame, a lifting hydraulic rod, and an upper fixed table. The rotation drive device's rotation motor directly drives the lower fixed table to rotate via the rotation rod, achieving uniform heating and quenching of the workpiece, avoiding the drawbacks of traditional soft belt drives. At the same time, the linear driver and electric lifter adjust the position and height of the heating ring, and the upper and lower fixed tables work together to clamp the workpiece, ensuring the stability of the quenching process.

[0006] The solution has limited adaptability and load-bearing capacity, and can only meet the needs of workpieces of conventional size. It is difficult to adapt to the stable processing of large and irregularly shaped workpieces. In addition, the solution lacks a supporting cooling system, temperature monitoring and closed-loop control, resulting in poor process continuity and accuracy. Moreover, it is single-function and cannot meet the needs of various quenching processes.

[0007] For example, Chinese Patent CN118127281A discloses a quenching machine tool that utilizes high-speed workpiece rotation to achieve quenching without soft strips. This solution utilizes high-speed workpiece rotation to achieve quenching without soft strips. The core of this quenching machine tool consists of multiple symmetrically arranged transformers (Transformer 1, Transformer 2...Transformer 8), matching busbars 1, 2...8, sensors 1, 2...8 mounted on the busbars, displacement sensors 1, 2...8, and temperature sensors 1 and 8. The temperature sensor consists of eight components: the workpiece is placed on a rotating disk with multiple equidistant slide rails and sliding limit posts; the rotating disk is driven by a rotary motor, and the workpiece speed is set to 5-20 r / min; the external power supply is provided by a transformer; the inductor heats the workpiece; the displacement sensor detects the distance between the inductor and the workpiece; and the temperature sensor monitors the heating temperature of the workpiece raceway. Its core principle is to achieve continuous heating by rotating the workpiece at high speed, so that the energy loss after the workpiece leaves the inductor is less than the energy imparted by the inductor, thereby achieving the purpose of quenching without soft strips through scanning quenching. The limit posts on the rotating disk can achieve self-centering of the workpiece.

[0008] The limitations of this technology are that it relies solely on the high-speed rotation of the workpiece and heating by multiple inductors to achieve quenching without soft strips. It does not have a segmented heating structure, resulting in low heating efficiency. Furthermore, the symmetrical layout of multiple inductors makes it difficult to cover the uniform heating requirements of the entire circumference of large ring-shaped workpieces, which can easily lead to temperature gradients. Summary of the Invention

[0009] To address the technical shortcomings of existing large bearing quenching equipment, such as low processing efficiency, poor adaptability to large workpieces, insufficient heating uniformity, incomplete cooling system, low process accuracy, and lack of closed-loop control, this invention provides a quenching system and method for processing wind turbine main bearings. It designs an integrated quenching equipment consisting of an industrial control computer, a main support system, a power supply system, a water system, and a control and monitoring system, and provides a quenching method adapted to this equipment.

[0010] The various systems work together to form a quenching process system of "precise positioning - multi-module controllable heating - dual-cycle intelligent cooling - full-process monitoring and control". The core innovations are reflected in: 1. The main support system adopts a symmetrical column + coaxial induction heating coil + three-jaw chuck centering structure, which is suitable for processing large ring-shaped workpieces such as wind turbine main bearings and ensures heating coaxiality; 2. The power system adopts a configuration of dual power supplies per column, with a total of eight power supplies for four columns. Combined with power closed-loop control, it achieves precise adjustment of heating power and supports segmented heating of a single column / simultaneous heating of multiple columns. 3. The water system is divided into a dual-circulation architecture of cooling water system and quenching spray system, both equipped with sensor monitoring and closed-loop cooling, which not only solves the overheating problem of equipment during long-term operation, but also achieves precise control of quenching cooling. 4. The control and monitoring system adopts the architecture of the "Siemens ONE system" to realize the integrated automation of servo positioning, power start and stop, water system control and process parameter monitoring, and the data of each link are interconnected to form a closed loop; 5. The induction heating coil adopts a copper hollow induction coil + independent cooling channel design, combined with the switchable cooling medium and adjustable flow structure of the quenching spray system to meet the customized needs of different quenching processes.

[0011] 6. The overall technical solution achieves high efficiency, uniformity, automation, and precision in the quenching of large wind turbine main bearings, solves the technical pain points of traditional scanning quenching and bainitic integral quenching, and is suitable for heat treatment processing of large and irregularly shaped ring workpieces.

[0012] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: a quenching system and method for processing wind turbine main bearings, including a turntable, a plurality of columns arranged circumferentially around the turntable, and a worktable rotatably arranged at the center of the turntable. The columns are provided with telescopic devices, and induction heating coils are installed at the telescopic ends of the telescopic devices. The top of the worktable is provided with a workpiece positioning and clamping mechanism for clamping the wind turbine main bearing. The plurality of induction heating coils are electrically connected to a plurality of power supply cabinets respectively. The induction heating coils include an induction load composed of induction coils. The power cabinet is equipped with a main power circuit. The main power circuit includes a thyristor rectifier bridge, which is electrically connected to a smoothing reactor. The smoothing reactor is electrically connected to an IGBT inverter bridge. The IGBT inverter bridge is electrically connected to a resonant capacitor. The resonant capacitor is electrically connected to a quenching transformer. The quenching transformer is electrically connected to an induction heating coil.

[0013] The beneficial effects of this invention are: 1. This quenching system for wind turbine main bearing processing, through the main support structure design of symmetrical columns + coaxial induction heating coils + three-jaw chuck, achieves precise centered positioning of large ring-shaped workpieces such as wind turbine main bearings, ensures the coaxiality of the workpiece and heating components, effectively avoids temperature gradients during heating, solves the problems of poor adaptability of existing equipment to large workpieces and insufficient heating uniformity, and significantly improves the hardness consistency and wear resistance of the workpiece after quenching. 2. This quenching system for wind turbine main bearing processing adopts a configuration of one column with dual power supplies, totaling eight power supplies across four columns, forming a closed-loop power control system. It supports two modes: segmented heating within a single column and synchronous heating between multiple columns. It can be flexibly switched according to workpiece size and quenching process requirements, significantly improving the quenching efficiency of large workpieces and solving the technical defects of slow traditional scanning quenching processing. At the same time, the power system is matched with an independent equipment cooling water system to avoid overheating problems caused by long-term full-load operation of the high-frequency power supply, thus extending the service life of the equipment. 3. The quenching system used for wind turbine main bearing processing is divided into a dual circulating water system for equipment cooling and quenching liquid spraying. Both systems are equipped with flow, temperature, and pressure sensors for monitoring and closed-loop control. This system can achieve continuous and efficient cooling of the equipment's heating elements and induction heating components. It can also switch the cooling medium and adjust the liquid spray flow and temperature according to the quenching process requirements to precisely control the cooling rate. This avoids the problem of pearlite and martensite mixing caused by improper selection / control of the cooling medium, and ensures the processing effect of processes such as bainite overall quenching. 4. The quenching system used for wind turbine main bearing processing adopts the control and monitoring architecture of the "Siemens ONE system" to realize integrated automated control of servo positioning, power start and stop, water system operation, and process parameter acquisition. Data from each system is interconnected and uploaded to the industrial control computer, realizing real-time monitoring, precise control, and parameter traceability of the entire quenching process. This solves the problems of poor process continuity and low accuracy of existing equipment and reduces human operation errors.

[0014] Based on the above technical solution, the present invention can be further improved as follows.

[0015] Furthermore, it also includes equipment cooling water systems and quenching spray systems; The equipment cooling water system includes a cooling water tank, a plate heat exchanger, a first inlet pipe, a return pipe, a filter, a flow and temperature sensor, and a pressure sensor. One end of the first inlet pipe is connected to the outlet of the cooling water tank, and the other end passes through the filter and the plate heat exchanger before entering the cooling channel inside the column. The return pipe connects the outlet of the cooling channel of the column to the return port of the cooling water tank. The flow and temperature sensor and the pressure sensor are respectively installed on the first inlet pipe. The quenching spray system includes a machine tool water tank, a second water inlet pipe, a quenching circulation pump, a quenching water pump, a water distributor, and water sprayers. The machine tool water tank is located below the turntable to collect quenching liquid. The inlet of the quenching circulation pump is connected to the machine tool water tank, and its outlet is connected to the inlet of the quenching water pump through the second water inlet pipe. The outlet of the quenching water pump is connected to the water distributor, and multiple outlets of the water distributor are respectively connected to multiple water sprayers. The water sprayers are installed on the column and face the workpiece on the worktable. The equipment cooling water system and the quenching spray system are electrically connected to the hydraulic station, the quenching water pump, the power supply cooling pump, the load cooling pump, the sensor cooling pump, and the sensor of the second water inlet pipe through cables.

[0016] The beneficial effects of adopting the above-mentioned further scheme are that it splits the water system into two independent circulation systems: an equipment cooling water system and a quenching spray system. This achieves separate control of equipment cooling and workpiece quenching cooling, avoiding mutual interference. The equipment cooling water system forms a closed-loop circulation with the cooling water tank as the core, equipped with multi-stage cooling pumps, plate heat exchangers, and filters to achieve efficient and continuous cooling of induction heating coils and power cabinet heating elements. The filters remove impurities from the water circuit, preventing blockage of the second water inlet pipe and scaling of cooling elements, ensuring the stability of the cooling effect. The quenching spray system adopts a dual-pump configuration of a quenching water pump and a quenching circulation pump. The quenching circulation pump, together with the plate heat exchanger, realizes the circulation cooling and reuse of the quenching liquid, saving water resources. At the same time, the water distributor divides the water circuit into multiple independently controlled channels, enabling differentiated spray cooling for different parts of the workpiece, adapting to the quenching requirements of irregularly shaped large wind turbine main bearings. Furthermore, both water circuits are connected in series with flow, temperature, and pressure sensors, which can monitor the water circuit operating parameters in real time, facilitating timely adjustment and avoiding the impact of abnormal cooling parameters on equipment operation and workpiece quenching quality.

[0017] Furthermore, it also includes a servo system, which is electrically connected to the electrical control cabinet and controls the rotation angle and speed of the worktable, enabling precise positioning and rotational heating of the workpiece within the induction heating coil. The control and monitoring system includes a main power switch, which is electrically connected to the electrical control system and the power supply system via cables. The electrical control system is electrically connected to the servo system, the power cabinet's start / stop control terminal, and the relay group via cables. The servo system is mechanically connected to the induction heating coil sensor and the mechanical movement mechanism of the load components.

[0018] The beneficial effects of adopting the above-mentioned further solutions are as follows: Functional control is achieved using the architecture of the "Siemens ONE system." The Siemens ONE system focuses on the positioning control of the servo system, the start / stop of the power cabinet, and I / O logic processing, ensuring the accuracy of the heating position and the timeliness of power control. The water system controlled by the Siemens ONE system is responsible for the control and data acquisition of sensors for each pump, hydraulic station, and second inlet water pipeline, achieving precise regulation of the cooling system. Simultaneously, the Siemens ONE system connects to the industrial control computer, allowing the uploading of full-process process parameters and equipment operating parameters to the industrial control computer, enabling real-time display, storage, and traceability of parameters. The main power switch provides unified power-off protection for the electrical control system and power system, improving the safety of equipment operation. The servo system is connected to the mechanical movement mechanism of the induction heating coil, enabling automated and precise adjustment of the heating position, adapting to the processing requirements of wind turbine main bearings of different sizes, and reducing errors from manual adjustment.

[0019] Furthermore, the column is a hollow frame structure, the induction heating coil is fixed to the front middle of the column by an adjustable bracket, and the workpiece positioning and clamping mechanism is installed on the workbench and coaxially arranged with the induction heating coil to radially limit and axially press the outer or inner ring of the wind turbine main bearing.

[0020] The beneficial effects of adopting the above-mentioned further solution are that several columns are fixedly connected to the induction heating coil through a bracket, and the heating component and the workpiece positioning and clamping mechanism are arranged coaxially. On the one hand, this ensures the structural stability of the induction heating coil, avoids changes in the heating gap caused by component shaking during the heating process, and ensures the stability of the heating power. On the other hand, the coaxial arrangement makes the distance between the workpiece circumference and the induction heating component consistent, realizing uniform heating of the entire circumference of the large annular wind turbine main bearing, effectively eliminating temperature gradients, avoiding deformation and cracking caused by insufficient local hardness and uneven stress after workpiece quenching, and improving the workpiece quenching quality.

[0021] Furthermore, the induction heating coil includes an induction coil arranged in a circular shape. The inner diameter of the induction coil matches the outer or inner diameter of the wind turbine main bearing to be processed, and it is fixed to a non-magnetic metal frame by an insulating support. The two ends of the induction coil are electrically connected to the secondary winding of the quenching transformer to form the induction load.

[0022] The beneficial effects of adopting the above-mentioned further solution are that the induction heating coil is composed of inductors evenly distributed along the circumference, and each inductor is equipped with an independent power adjustment module, which can individually control the heating power of each part of the workpiece circumference. Even if there are slight dimensional deviations in the workpiece, uniform heating can be achieved through power compensation, further improving the heating uniformity. The induction coil of the inductor adopts a hollow copper structure and forms an internal cooling channel, which is connected to the inlet and outlet water pipes of the equipment cooling water system to achieve self-cooling of the induction coil, avoid overheating and burnout caused by long-term high-frequency operation of the induction coil, extend the service life of the induction heating component, and at the same time, the high conductivity of copper material can improve the electromagnetic induction heating efficiency and reduce energy consumption.

[0023] Furthermore, a manual ball valve for adjusting the flow rate of the quenching liquid is provided on the second water inlet pipe. The ball valve is located on the inlet side of the quenching water pump and is used to coarsely adjust the spray pressure of the water sprayer during the equipment commissioning phase.

[0024] The beneficial effects of adopting the above-mentioned further solution are as follows: the water sprayer is fixed inside the induction heating coil, so that the position of the spray cooling is matched with that of the induction heating, realizing immediate and precise cooling of the workpiece after heating, and ensuring the rhythm of the quenching process; the water sprayer is connected in series with the solenoid valve and the solenoid valve is electrically connected to the water system, realizing automated and precise control of the spray flow rate and spray timing, replacing manual adjustment and reducing operational errors; the quenching spray system is connected to the power cooling pump, which can use the pressure of the equipment cooling system to ensure the stability of the spray, while realizing unified management of the water circuit, simplifying the layout of the second water inlet pipe of the equipment, and reducing the difficulty of equipment maintenance.

[0025] Furthermore, the first water inlet pipe is vertically arranged inside the column, and the return water pipe is led out from the top of the column and returns to the cooling water tank through the filter, forming a closed-loop cooling circuit for continuous cooling of the induction heating coil and the electrical components inside the column.

[0026] The beneficial effects of adopting the above-mentioned further solution are that the second water inlet pipe is laid along the side of the column and fixed to the column with pipe clamps, which makes full use of the space structure of the equipment, making the layout of the second water inlet pipe neat and orderly, and can avoid collision damage to the second water inlet pipe caused by equipment operation and workpiece hoisting, thus improving the structural stability of the second water inlet pipe. The return water pipe is connected to the cooling water tank after passing through the filter, which can filter out impurities, iron filings and other impurities in the water circuit, preventing impurities from entering the cooling water tank and clogging the internal cooling channels of the cooling pump and induction coil, ensuring the circulation efficiency and cooling effect of the equipment's cooling water system, and forming a closed-loop second water inlet pipe to realize the reuse of cooling water, save water resources and reduce processing costs.

[0027] The present invention also provides a quenching method for use in a quenching system, characterized by comprising the following steps: S1: Clean the oil, rust and oxide scale from the surface of the workpiece to be quenched, and polish it until smooth; S2: The pre-treated workpiece is hoisted onto the turntable and clamped in the center by the workpiece positioning and clamping mechanism; S3: Input preheating power, preheating time, heating power, heating time, cooling water flow rate, and quenching spray flow rate parameters through the Siemens ONE system; S4.: Set the heating position reference point, start the automatic mode, the servo system moves the sensor to the heating position, controls the power supply group of the power system to work, and heats the workpiece through the induction heating coil composed of the sensor and load components. S5: During the heating process, the load cooling pump and the inductor cooling pump remain running, and the quenching pump adjusts the liquid spray cooling according to the method rhythm.

[0028] The beneficial effects of adopting the above-mentioned further solution are that the quenching method is highly compatible with the structure and function of the quenching system, forming a standardized and automated quenching process. The pretreatment step can remove oil, rust, and oxide scale from the workpiece surface, avoiding impurities from affecting the efficiency of induction heating and the surface quality of the workpiece after quenching. The standardized operation of workpiece positioning and clamping ensures heating coaxiality, avoiding uneven heating from the source of the process. All process parameters are uniformly input through the electrical control system, realizing precise preset of parameters for each stage of preheating, heating, and cooling, replacing manual step-by-step adjustment and improving process continuity. The continuous start of the cooling pump and the rhythmic control of the quenching pump during the heating process not only ensure the safe operation of the equipment, but also accurately match the cooling rhythm of the quenching process, achieving seamless connection of "heating-cooling", effectively improving the quenching processing efficiency and processing quality of large wind turbine main bearings. Moreover, this method is simple to operate and easy to promote and apply in industrial applications.

[0029] Furthermore, in step S4, the workpiece heating method includes segmented heating within a single column and synchronous heating between multiple columns.

[0030] The beneficial effects of adopting the above-mentioned further solution are that it supports two heating methods: segmented heating within a single column and synchronous heating between multiple columns. This allows for flexible switching based on the size and specifications of the wind turbine main bearing and the quenching process requirements. For large-sized, thick-walled wind turbine main bearings, segmented heating within a single column enables gradient heating along the workpiece's axial direction, ensuring heating depth and uniformity. For wind turbine main bearings of standard sizes, synchronous heating between multiple columns enables rapid heating throughout the entire circumference, significantly improving processing efficiency. The design of these two heating methods allows the quenching system to adapt to the processing needs of wind turbine main bearings of different specifications, enhancing the equipment's versatility and adaptability, and solving the problem of existing quenching equipment having limited functionality and failing to meet diverse process requirements.

[0031] Furthermore, in step S5, the cooling system switches the type of cooling medium and adjusts the spray flow rate and temperature according to the requirements of the quenching process.

[0032] The beneficial effects of adopting the above-mentioned further solutions are that the cooling system can switch the type of cooling medium, adjust the spray flow rate and temperature according to the quenching process requirements, and achieve precise and customized control of the quenching cooling rate: for the bainitic integral quenching process, the appropriate cooling medium can be switched and adjusted to the critical cooling rate to achieve slow cooling of the workpiece to the isothermal zone, avoiding the mixing of pearlite and martensite and ensuring the formation of bainite structure; for conventional quenching processes, the spray flow rate can be increased and the cooling medium temperature can be reduced to achieve rapid cooling of the workpiece and improve the workpiece hardness and wear resistance; at the same time, the flexible adjustment of cooling parameters makes the system not only suitable for the quenching of wind turbine main bearings, but also adaptable to the different quenching process requirements of other large ring bearings, further expanding the application range of the equipment. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the quenching equipment of the present invention; Figure 2 This is a schematic diagram of the turntable structure of the quenching equipment of the present invention; Figure 3 This is a circuit topology diagram of the power supply system of the present invention; Figure 4 This is a schematic diagram of the cooling water system of the device of the present invention; Figure 5 This is a schematic diagram of the water circuit of the quenching spray system of the equipment of the present invention; Figure 6 This is a block diagram showing the overall architecture of the electronic control and power supply system of the present invention.

[0034] In the diagram: 11. Column; 12. Turntable; 13. Workbench; 14. Induction heating coil; 15. Power supply cabinet; 16. Workpiece positioning and clamping mechanism; 17. Servo system; 21. Thyristor rectifier bridge; 22. Smoothing reactor; 23. IGBT inverter bridge; 24. Resonant capacitor; 25. Quenching transformer; 26. Inductive load; 31. Cooling water tank; 32. Plate heat exchanger; 33. Return water pipeline; 34. Flow and temperature sensor; 35. Filter; 36. Pressure sensor; 37. First water inlet pipeline; 41. Machine tool water tank; 43. Quenching circulating pump; 44. Quenching water pump; 45. Water sprayer; 46. Water distributor; 47. Ball valve; 48. Second water inlet pipeline. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Example 1, by Figure 1-6 This invention provides a quenching system and method for processing wind turbine main bearings. The system and method include an industrial control computer, a main support system, a power supply system, a water system, and a control and monitoring system. These systems work collaboratively through mechanical and electrical connections. This embodiment is suitable for processing MW-level wind turbine main bearings. The core specifications are: a workpiece positioning and clamping mechanism 16 with a clamping diameter range of 1500-5000mm; a worktable 13 capable of low-speed rotation of 0-5r / min; a column 11 with a load-bearing capacity ≥50t; an induction heating coil 14 with a single inductor power adjustment range of 50-600kW; a copper hollow induction coil cooling channel with a water flow rate of 2-4m / s; a power supply output voltage of 0-500V and a frequency of 3-8kHz; and a quenching transformer 25 with a turns ratio of 10:1.

[0037] The main support system includes a turntable 12 and four sets of columns 11 symmetrically arranged around the turntable 12. Induction heating coils 14 are mounted on the columns 11. A worktable 13 is located at the bottom of the turntable 12, and a workpiece positioning and clamping mechanism 16 is located at the top of the turntable 12. The ends of the four columns 11 closest to the workpiece are fixedly connected to the induction heating coils 14 via brackets, and the induction heating coils 14 and the workpiece positioning and clamping mechanism 16 are arranged coaxially. (Whereinafter, the turntable 12, worktable 13, and clamping mechanism 16 are the rotary table 2, raceway workpiece 8, and clamping column 6 described in patent CN210506459U). The induction heating coil 14 consists of four inductors evenly distributed along the circumference. Each inductor is equipped with an independent power adjustment module. The induction coil of the inductor adopts a hollow copper structure, forming an internal cooling channel, and the two ends of the internal cooling channel are connected to the first water inlet pipe and the return water pipe 33, respectively. The workpiece positioning and clamping mechanism 16 adopts a chuck structure to achieve the centering positioning and clamping of the workpiece. The workpiece positioning and clamping mechanism 16 is a three-jaw chuck, which can ensure that the axis of the workpiece coincides with the axis of the induction heating coil 14. The chuck has a built-in displacement sensor, which can provide feedback on the clamping position signal.

[0038] The power supply system includes a power cabinet 15 and an induction heating coil 14. The induction heating coil 14 is sleeved on the outside of the workpiece. The power cabinet 15 includes four preheating power supplies and four heating power supplies. Each column 11 is connected to one preheating power supply and one heating power supply. The power supply connected to the same column 11 is connected to the corresponding heating unit of the induction heating coil 14 through a cable. The power supply system includes a main control board. The main control board is electrically connected to the rectifier-inverter bridge. The rectifier-inverter bridge is electrically connected to the quenching load. The rectifier-inverter bridge and the main control board are both electrically connected to the voltage and current transmitter board. The quenching load and the main control board are both electrically connected to the quenching transformer 25, forming a power closed-loop control with a power regulation accuracy of ±1kW.

[0039] Example 2: Based on Example 1, the water system includes four sets of equipment cooling water systems and four sets of quenching spray systems. In this example, the specifications of the second water inlet pipe are DN32 (first water inlet pipe) and DN50 (return water pipe / second water inlet pipe for quenching spray). The rated flow rate of the power supply cooling pump / load cooling pump / sensor cooling pump is 50m³ / h. 3 / h, Quenching water pump 44 rated flow 80m³ / h 3 The heat exchange efficiency of plate heat exchanger 32 is ≥90% per hour; the filtration accuracy of filter 35 is 50μm; the sensor detection accuracy is: temperature ±1℃, flow rate ±0.5m³ / h. 3 / h, pressure ±0.01MPa, solenoid valve response time ≤0.5s.

[0040] All four sets of equipment cooling water systems are connected to the cooling water tank 31. The cooling water tank 31 is fixedly connected to the turntable 12 below by a bracket. The cooling water tank 31 is connected to four first water inlet pipes. The first water inlet pipes are connected to the power cooling pump, the load cooling pump and the inductor cooling pump in sequence through flange interfaces. The cooling pumps are connected to the induction heating coil 14 and the heating element inside the power cabinet 15 through the first water inlet pipes respectively. The other end of the induction heating coil 14 and the power cabinet 15 is connected to the return water pipe 33. The other end of the return water pipe 33 is connected to the cooling water tank 31. The first water inlet pipe is laid along the side of the column 11 and fixedly connected to the column 11 by pipe clamps. The return water pipe 33 is connected to the cooling water tank 31 after passing through the filter 35, forming a closed loop second water inlet pipe. The first inlet water pipe and the return water pipe 33 are both connected in series with a flow and temperature sensor 34 and a pressure sensor 36. The return water pipe 33 is also connected in series with a filter 35 and a plate heat exchanger 32. The equipment cooling water system is turned on 10 seconds before the power cabinet 15 is started, realizing the protection logic of "cooling first and then heating".

[0041] All four sets of quenching spray systems are connected to the machine tool water tank 41. The machine tool water tank 41 is connected to eight second water inlet pipes, four of which are connected to quenching water pumps 44 and the other four are connected to quenching circulation pumps 43. The water output of each quenching water pump 44 is divided into 18 individually controlled water paths by a water distributor 46, and finally connected to a water sprayer 45. The workpiece is cooled by controlling the water sprayer 45. The other end of the quenching circulation pump 43 is connected to the plate heat exchanger 32 and the machine tool water tank 41 in sequence. After the quenching liquid is cooled by the plate heat exchanger 32, the quenching circulation pump 43 circulates back to the machine tool water tank 41 through the second water inlet pipe 48.

[0042] The control and monitoring system includes a main power switch, which is electrically connected to the electrical control system (Siemens ONE system) and the power supply system via cables. The electrical control system is electrically connected to the servo system 17, the start / stop control terminal of the power cabinet 15, and the relay group via cables. The servo system 17 is connected to the sensor of the induction heating coil 14 and the mechanical movement mechanism of the load component. The water system controlled by the Siemens ONE system is electrically connected to the hydraulic station, the quenching water system control cabinet, the power cooling pump, the load cooling pump, the sensor cooling pump, and the second inlet water pipe sensor via cables. The Siemens ONE system is connected to the industrial control computer via Profinet industrial Ethernet, with a data exchange frequency of 100ms / time. The industrial control computer achieves data communication through the OPCUA protocol, and the process parameter storage period is ≥1 year.

[0043] The quenching spray system is connected to the power cooling pump through the second water inlet pipe 48. The water sprayer 45 is fixedly connected to the inside of the induction heating coil 14 (sensor, load component) by a bracket. According to the process control requirements, the present invention can select valves for the water sprayer 45. In the manual debugging stage, a ball valve 47 is used to achieve coarse flow adjustment. In the automatic processing stage, an electromagnetic valve is electrically connected to the water system to achieve automatic and precise flow control. The response time of the electromagnetic valve is ≤0.5s.

[0044] The control and monitoring system adopts the "Siemens ONE system" architecture. The Siemens ONE system manages the servo system 17, power start / stop control, I / O logic processing, and data interaction with the industrial control computer. The Siemens ONE system is electrically connected to the push-button switches and arc protection devices through relay groups to form an I / O logic control loop. The water system controlled by the Siemens ONE system is responsible for water system control. The Siemens ONE system uses the S7-1500 series PLC.

[0045] In this embodiment, the electrical control system adopts the Siemens ONE system. When the workpiece is clamped, the hydraulic station outputs pressure oil to drive the three-jaw chuck-type workpiece positioning and clamping mechanism 16 to clamp radially. The displacement sensor built into the chuck feeds back the clamping position signal to the Siemens ONE system. The system then controls the worktable 13 to rotate at a low speed of 1r / min. The laser alignment sensor detects the coaxiality between the workpiece axis and the induction heating coil 14 axis. If the deviation is >0.1mm, the worktable 13 automatically fine-tunes until the coaxiality meets the standard and then locks.

[0046] The number of columns 11, sensors, power supplies, and water systems in this invention can be flexibly adjusted according to the size and specifications of the wind turbine main bearing, while the core design principle remains unchanged: When adapting to small wind turbine main bearings with an outer diameter <1500mm, two sets of symmetrical columns 11, two sensors, and two sets of preheating / heating power supplies are used, and the water system and control and monitoring system are simultaneously reduced to two sets; when adapting to ultra-large wind turbine main bearings with an outer diameter >5000mm, six or eight sets of symmetrical columns 11 are used, with six or eight sensors and six or eight sets of power supplies correspondingly configured, and the water system is increased to six or eight sets. The sensors of the induction heating coil 14 are evenly distributed along the circumference, and the control and monitoring system only needs to expand the control channels of the power cabinet 15.

[0047] Working Principle: This quenching system for wind turbine main bearings uses an industrial control computer as its core, relying on the mechanical and electrical linkage of the main support system, power system, water system, and control and monitoring system to achieve integrated automated quenching operations, including "precise workpiece positioning, controllable induction heating, intelligent cooling process, and full-process parameter monitoring." Each system works collaboratively according to preset process logic, adapting to the quenching requirements of large ring-shaped workpieces such as wind turbine main bearings. The core working logic is as follows: After the system starts up, the main power switch first provides stable power to the electrical control system (Siemens ONE system) and the power supply system. The electrical control system then triggers a full equipment self-test, completing the reset and troubleshooting of modules such as the servo system, each cooling pump / quenching pump, the second water inlet pipe sensor, and the power cabinet. After the self-test is completed without any abnormalities, the equipment enters the standby state and can start the quenching process. The specific process execution is divided into the following stages: First, the surface of the wind turbine main bearing workpiece is pretreated by cleaning off oil, rust, and scale, and polishing it smooth to avoid impurities affecting the induction heating efficiency and the quality of the quenched surface. Then, the pretreated workpiece is hoisted onto the turntable. The ONE system of the control and monitoring system drives the hydraulic station to close the three-jaw chuck-type workpiece positioning and clamping mechanism on the top of the turntable, achieving centered clamping of the workpiece and ensuring that the workpiece axis is completely aligned with the axis of the induction heating coil. The worktable at the bottom of the turntable can be finely adjusted according to process requirements to ensure that the heating gap between the workpiece circumference and the inductor is uniform, laying the foundation for uniform heating in the future.

[0048] Operators input all quenching process parameters into the Siemens ONE system via an industrial control computer, including preheating power, preheating time, heating power, heating time, equipment cooling water flow rate / pressure, and quenching spray flow rate / pressure. At the same time, they select the workpiece heating method (segmented heating within a single column / synchronous heating between multiple columns) and the type of cooling medium. After summarizing the parameters, the Siemens ONE system sends parameter commands to the power system, water system, and servo system respectively, completing the process parameter preset of each module and ensuring that each system operates according to a unified process rhythm.

[0049] After the process parameters are set, the operator sets the heating position reference point on the industrial control computer and starts the automatic mode. The Siemens ONE system immediately controls the servo system to move the inductor of the induction heating coil along the column to the preset heating position and precisely adjust it to the optimal heating gap. Subsequently, the power system starts the preheating power supply of the corresponding column according to the instruction. The current is converted by the main circuit components such as the thyristor rectifier bridge, smoothing reactor, and IGBT inverter bridge, and then sent to the inductor of the induction heating coil through the quenching transformer to achieve overall preheating of the workpiece. When the workpiece reaches the preset preheating temperature and is held at pressure for a specified time, the power system automatically switches to the heating power supply and carries out the heating operation according to the selected heating method: if it is segmented heating within a single column, the dual power supply corresponding to a single column performs axial layered heating of the thick-walled wind turbine main bearing, and the power of each segment is dynamically controlled by an independent power adjustment module; if it is synchronous heating between multiple columns, the eight power supplies of the four columns work simultaneously to achieve rapid and uniform heating of the entire circumference of the workpiece. During the heating process, the power system uses a closed-loop power control system consisting of the main control board, voltage and current transmitter board and quenching transformer to monitor changes in circuit voltage and current in real time, dynamically adjust the output power of the rectifier-inverter bridge, avoid temperature gradients or overheating of the workpiece, and ensure heating stability.

[0050] Throughout the heating process, the Siemens ONE system continuously activates the power cooling pump, load cooling pump, and sensor cooling pump of the equipment's cooling water system. The cooling water in the cooling water tank is delivered through the first inlet pipe to the cooling channels inside the heating elements and the copper hollow induction coil of the induction heating coil inside the power cabinet, thus completing the cooling of the core heating components of the equipment. The cooled water, after absorbing heat, flows back through the return pipe, passing through a filter to remove iron filings and impurities from the water path, and then through a heat exchanger to cool down. Flow, temperature, and pressure sensors along the return path collect water path parameters in real time and feed them back to the ONE system. If the parameters deviate from the preset values, the system will automatically adjust the cooling pump speed, forming a closed-loop control of equipment cooling. After the workpiece is heated to the preset temperature and held for the specified time, the quenching spray system is triggered according to the process rhythm. The quenching water pump divides the cooling medium in the machine tool water tank into multiple individually controlled water channels through a water distributor. The workpiece heating surface is precisely cooled by spraying water through the sprayers fixed inside the induction heating coil. The type of cooling medium can be switched according to the quenching process requirements (such as bainitic integral quenching / conventional quenching). The spray flow rate is adjusted by the solenoid valve, and the temperature of the cooling medium is controlled by the plate heat exchanger in conjunction with the quenching circulation pump to achieve precise control of the critical cooling rate or rapid cooling rate. At the same time, the quenching circulation pump returns the used cooling medium to the machine tool water tank after cooling by the plate heat exchanger, realizing the recycling of the cooling medium and saving processing costs.

[0051] Throughout the quenching process, various sensors in the control and monitoring system continuously collect operational data: tracking, proximity switches, and arc protection sensors transmit signals such as equipment mechanical position and arcing anomalies to the Siemens ONE system; simultaneously, flow, temperature, and pressure sensors transmit water system operating parameters through the water system to the Siemens ONE system. All data is ultimately aggregated and uploaded to the industrial control computer, enabling real-time display and storage of process and equipment operating parameters. If the system detects arcing, blockage in the second water inlet pipe, excessive temperature, or abnormal pressure, it will immediately trigger an audible and visual alarm, and automatically cut off the power to the corresponding module or stop the pump operation to ensure the safety of the equipment and the quenching process. Once the workpiece has cooled and met the quenching process requirements, the system automatically issues a process completion notification. The Siemens ONE system controls the servo system to reset the sensors to their initial positions, driving the hydraulic station to release the workpiece positioning and clamping mechanism, allowing the operator to lift the quenched workpiece.

[0052] After the quenching process is completed, the industrial control computer will store the process parameters of the entire quenching process, which will facilitate subsequent process optimization, quality control and data traceability. The operator can trigger the equipment reset command through the industrial control computer, the main power switch will cut off the power supply to the corresponding module as needed, the water system will complete the return of residual liquid in the second water inlet pipe, all moving parts will return to their initial positions, the equipment will enter the standby state, and the next batch of workpieces can be quenched.

[0053] New site implementation steps: Step 1: Clean the oil, rust and oxide scale from the surface of the workpiece to be quenched, and polish it until smooth; Step 2: Hoist the pre-treated workpiece onto the turntable and clamp it in the center using the workpiece positioning and clamping mechanism; Step 3: Input the preheating power, preheating time, heating power, heating time, cooling water flow rate, and quenching spray flow rate parameters through the Siemens ONE system; Step 4: Set the heating position reference point, start the automatic mode, the servo system moves the sensor to the heating position, and controls the heating power supply group of the power supply system to work. The induction heating coil composed of the sensor and load components heats the workpiece in sections within a single column or synchronously between multiple columns. Step 5: During the heating process, the load cooling pump and the sensor cooling pump remain running, and the quenching pump switches the cooling medium type according to the quenching process requirements, and adjusts the spray flow rate and temperature to ensure precise control of the spray cooling.

[0054] In summary, the quenching system for wind turbine main bearings provided by this invention, through multi-system collaborative design and modular control, solves many technical pain points of traditional quenching equipment in processing large wind turbine main bearings, achieving significant improvements in processing efficiency, quenching quality, equipment stability, and resource utilization. This system is adaptable to the processing of MW-class wind turbine main bearings with outer diameters of 1500-5000mm, improving processing efficiency by more than 40% compared to traditional scanning quenching equipment. The dual-mode design of segmented heating within a single column and synchronous heating between multiple columns can adapt to wind turbine main bearings of different wall thicknesses and materials. The circumferential hardness deviation of the workpiece after quenching is ≤2HRC, and the axial quenching layer depth is uniform. Uniformity deviation ≤0.5mm, no defects such as soft bands or quenching cracks, and workpiece quenching qualification rate increased to over 99.5%; the equipment adopts a dual circulating water system and power closed-loop control design, which can achieve 72 hours of continuous full-load operation. The temperature rise of power cabinet 15 and induction heating coil 14 can be controlled within 45℃. The monthly average failure rate of the equipment is ≤0.5%. The quenching fluid recycling design reduces water consumption by 60%. Independent power adjustment and precise temperature and flow control design reduce energy consumption per workpiece by 30%. At the same time, the Siemens ONE system architecture realizes full-process automated control and parameter traceability, which greatly improves the industrial application value and process adaptability of the equipment.

[0055] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0056] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A quenching system for machining wind turbine main bearings, characterized in that: The system includes a turntable (12), several columns (11) arranged around the turntable (12), and a worktable (13) rotatably located at the center of the turntable (12). The columns (11) are equipped with telescopic devices, and the telescopic ends of the telescopic devices are equipped with induction heating coils (14). The top of the worktable (13) is equipped with a workpiece positioning and clamping mechanism (16) for clamping the wind turbine main bearing. Several induction heating coils (14) are electrically connected to several power cabinets (15). Each induction heating coil (14) includes an induction load (26) composed of induction coils. The power cabinet (15) is equipped with a main power circuit. The main power circuit includes a thyristor rectifier bridge (21). The thyristor rectifier bridge (21) is electrically connected to a smoothing reactor (22). The smoothing reactor (22) is electrically connected to an IGBT inverter bridge (23). The IGBT inverter bridge (23) is electrically connected to a resonant capacitor (24). The resonant capacitor (24) is electrically connected to a quenching transformer (25). The quenching transformer (25) is electrically connected to an induction heating coil (14).

2. The quenching system for processing wind turbine main bearings according to claim 1, characterized in that: It also includes the equipment cooling water system and the quenching spray system; The equipment cooling water system includes a cooling water tank (31), a plate heat exchanger (32), a first inlet pipe (37), a return pipe (33), a filter (35), a flow and temperature sensor (34), and a pressure sensor (36). One end of the first inlet pipe (37) is connected to the outlet of the cooling water tank (31), and the other end is connected to the cooling channel inside the column (11) after passing through the filter (35) and the plate heat exchanger (32). The return pipe (33) connects the outlet of the cooling channel of the column (11) to the return port of the cooling water tank (31). The flow and temperature sensor (34) and the pressure sensor (36) are respectively installed on the first inlet pipe (37). The quenching spray system includes a machine tool water tank (41), a second water inlet pipe (48), a quenching circulation pump (43), a quenching water pump (44), a water distributor (46), and water sprayers (45). The machine tool water tank (41) is located below the turntable (12) to collect quenching liquid. The inlet of the quenching circulation pump (43) is connected to the machine tool water tank (41), and the outlet is connected to the inlet of the quenching water pump (44) through the second water inlet pipe (48). The outlet of the quenching water pump (44) is connected to the water distributor (46). Multiple outlets of the water distributor (46) are respectively connected to multiple water sprayers (45). The water sprayers (45) are installed on the column (11) and face the workpiece on the worktable (13).

3. A quenching system for processing wind turbine main bearings according to claim 2, characterized in that: It also includes a servo system (17), which is electrically connected to the power cabinet (15) and controls the rotation angle and speed of the worktable, so that the workpiece is accurately positioned and uniformly scanned and heated under the surrounding induction heating coil.

4. A quenching system for processing wind turbine main bearings according to claim 1, characterized in that: The column (11) is a hollow frame structure. The induction heating coil (14) is fixed to the front middle of the column (11) by an adjustable bracket. The workpiece positioning and clamping mechanism (16) is installed on the workbench (13) and coaxially arranged with the induction heating coil (14) to radially limit and axially press the outer or inner ring of the wind turbine main bearing.

5. A quenching system and method for processing wind turbine main bearings according to claim 1, characterized in that: The induction heating coil (14) includes an induction coil arranged in a ring shape. The inner diameter of the induction coil matches the outer or inner diameter of the wind turbine main bearing to be processed and is fixed to a non-magnetic metal frame by an insulating support. The two ends of the induction coil are electrically connected to the secondary winding of the quenching transformer (25) to form the induction load (26).

6. A quenching system for processing wind turbine main bearings according to claim 2, characterized in that: The second water inlet pipe (48) is equipped with a manual ball valve (47) for adjusting the flow rate of the quenching liquid. The ball valve (47) is located on the inlet side of the quenching water pump (44).

7. A quenching system for processing wind turbine main bearings according to claim 2, characterized in that: The first water inlet pipe (37) is vertically arranged inside the column (11), and the return water pipe (33) is led out from the top of the column (11) and returned to the cooling water tank (31) through the filter (35), forming a closed-loop cooling circuit.

8. A quenching method applied to the quenching system according to any one of claims 1-7, characterized in that, Includes the following steps: S1: Clean the oil, rust and oxide scale from the surface of the workpiece to be quenched, and polish it until smooth; S2: The pre-treated workpiece is hoisted onto the turntable and clamped in the center by the workpiece positioning and clamping mechanism; S3: Input preheating power, preheating time, heating power, heating time, cooling water flow rate, and quenching spray flow rate parameters through the electronic control system; S4.: Set the heating position reference point, start the automatic mode, the servo system moves the sensor to the heating position, and controls the heating power supply group of the power supply system to work, heating the workpiece through the induction heating coil composed of the sensor and load components; S5: During the heating process, the load cooling pump and the inductor cooling pump remain running, and the quenching pump adjusts the liquid spray cooling according to the method rhythm.

9. A quenching method based on the quenching system of any one of claims 8, characterized in that: In step S4, the workpiece heating method includes segmented heating within a single column / synchronous heating between multiple columns.

10. A quenching method based on any one of the quenching systems described in claim 8, characterized in that: In step S5, the quenching pump switches the cooling medium type and adjusts the spray flow rate and temperature according to the quenching process requirements.

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